all: run go generate during ci builds to check all files updated (#2372)

### What
Run `go generate` during ci builds.

### Why
We use `go generate` to trigger builds of our bindata files for SQL
migrations but we don't have any broad checks on CI that ensure that the
generated files are up to date. This ensures whenever we make a change
to an input file to code generation that the generated file is updated
in the same change/pull-request.

We achieve this to some degree in some apps, like Horizon, where we have
a test that checks that the generated data bytes match the bytes on
disk, but this is only in one app, requires us to write a test in each
app, and doesn't prevent diffs caused by environmental changes like us
upgrading the version of the go-bindata tool.

.circleci/config.yml

@@ -14,6 +14,14 @@ commands:
           name: Run gofmt
           command: ./gofmt.sh
 
+  # gogenerate validates that any generated code has been updated if needed.
+  gogenerate:
+    steps:
+      - checkout
+      - run:
+          name: Check generated code
+          command: ./gogenerate.sh
+
   # govet does govet checks in the entire codebase.
   govet:
     steps:
@@ -144,6 +152,7 @@ jobs:
       - install_go_deps
       - check_go_deps
       - gofmt
+      - gogenerate
       - govet
       - staticcheck
 

gogenerate.sh

@@ -0,0 +1,17 @@
+#! /bin/bash
+set -e
+
+# Check if go-bindata is installed, if not install it.
+command -v go-bindata >/dev/null 2>&1 || (
+  dir=$(mktemp -d)
+  pushd $dir
+  go mod init tool
+  go get github.com/kevinburke/go-bindata/[email protected]+incompatible
+  popd
+)
+
+printf "Running go generate...\n"
+go generate ./...
+
+printf "Checking for no diff...\n"
+git diff --exit-code || (echo "Files changed after running go generate. Run go generate ./... locally and update generated files." && exit 1)